Eskoms Experiences in Renewable Energy in South Africa

1
Eskoms Experiences in Renewable Energy in South
Africa

• Louis van Heerden, PhD (Pr.Sci. Nat)
• Corporate Specialist Renewable Energy
• Louis.VHeerden_at_eskom.co.za

2
History of Eskom renewable energy

• The Government Gazette of 6 March 1923 announced
  the establishment of The Electricity Supply
  Commission (Escom), effective from 1 March 1923
• The hydro station in the Sabie River came into
  commercial operation in mid-1927. The Sabie River
  Gorge hydro station was the first station
  designed by Escom engineers
• 1965-1967 Cahora Bassa hydro-electric power
  station on the Zambezi River, in Mozambique
  (between South African and Portuguese
  governments) It was intended to supply electrical
  power along a 1 400 km route to South Africa -
  first power transmitted from Cahora Bassa in May
  1975
• Gariep hydro power station started feeding into
  Escoms transmission system in 1971
• Vanderkloof, a similar hydro power station, was
  commissioned in 1977 as another feature of the
  Orange River Project

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Direction Past Present
Some Drivers Past Present
Renewables Focus Off-grid programmes (schools
electrification, energisation residential
non-grid electrification), planning systems
late 90s awareness of grid options
Focus on both grid and non-grid options, resource
quantification understanding, pilot projects
feasibility studies Increased efforts w.r.t. SWH
Implementation focus on grid only, resource
technology preferences, feasibility studies and
commercial implementation. Rollout of SHW systems
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Understanding the resource

• Critical to any renewable energy based project is
  a thorough understanding of the resource.
• Initial Eskom activities in early 2000 focussed
  on obtaining a high-level understanding of what
  the various resource potentials are and what
  their geographic nature is, using largely
  existing data from various sources.
• This allowed the identification of high promise
  areas or hot spots. Subsequent to this early
  work, specific resource assessment programmes
  have been initiated around the various sources to
  narrow down the hot spots while also obtaining
  data at a sufficient confidence level to enable
  bankable production estimates.
• Hence many measurement sites have records in
  excess of 5 years.
• Vital to obtaining data of a high confidence
  level is the use of state of the art equipment,
  adherence to standards, monitoring and
  maintenance of the measurement stations.
• Specific resource measurements ongoing include
  solar, wind, ocean current and wave.

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Resource Availability - Wind Energy Resource

• National Resource
• The wind resource can be described as moderate
  with the East and West Coast regions having an
  avg. resource of app. 4 to 6m/s per annum _at_ a
  height of 10m or 6 to 8 m/s _at_ 50m.
• The wind is extremely seasonal and varied,
  resulting in relatively low avg. capacity factors
  between 15 and 25, though higher capacity factor
  sites exist.

Ref. NASA
6
Resource Availability - Ocean Energy Resource

• RSA - Good wave potential along certain coastal
  areas, comparable to international high-resource
  areas.
• The highest wave power potential, kW/m, occurs
  off-shore.
• The highest wave power generation occurs during
  the austral winter months, i.e. June, July and
  August
• The largest wave power yield (between 35 and 40
  kW/m) is concentrated along the South and South
  East coasts.
• Significant energy source in the form of the
  Agulhas current.
• Initial findings indicate a significant resource
  capable of delivering capacities sin the GW range
• Ocean currents measured ranged from 1-2 m/s2.
• Limited tidal resource.

Ref. Ocean Power Delivery

Ref. Ocean Power Delivery
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Resource Availability - Solar Energy

• South Africa experiences
• some of the highest levels
• of solar radiation in the
• world.
• The average daily solar
• radiation in South Africa
• varies between 4.5 and
• 6.5 kWh/m2 (16 and 23
• MJ/m2), with excellent
• areas such as Upington
• - 8.17 kWh/m2/day.

Ref oynot.com
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Micro-Hydro Resource
Ref. RSA Renewable Energy White Paper
Installed Capacity (small/mini/micro and pico
hydropower) 33.92MW Potential for
development Firmly established 69MW, additional
long-term 94MW Main opportunities exist for mini
and micro systems (lt1MW), decreasing has the size
increases (small and large).
Ref. RSA Renewable Energy White Paper
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Biomass Resource

• The biomass potential for can be divided into
  three groups, that of wood, agricultural and
  grass residues.
• The wood biomass includes commercial plantations,
  sawmills, pulp mills, harvestable woodlands,
  alien vegetation and deciduous tree offcuts.
• The crop residues includes maize, wheat, sorghum,
  sunflowers and sugarcane.
• Grasses are represented by the woodland and
  savanna biomes of South Africa as defined by the
  NBI Institute.
• Estimates indicate that there is potentially 1.26
  billion GJ of energy available annually from
  biomass residues. Biomass energy could thus
  theoretically provide 50 of the national
  demand.
• Recent developments have seen implementation and
  development of landfill gas projects with
  projects planned around MSW.

Ref. RSA Renewable Energy White Paper
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Experience to date - Wind
Resource assessment 1999-2003 compilation of Wind
Atlas 2003 onward actual resource measurements
and future site evaluation. Experience in all
aspects of site development including resource
modelling, turbine layouts and production
estimation.
Research 1998 2000 Initial technology research
and evaluation 2002/2003 Klipheuwel ROD and
installation of 3 turbines 2003-2006 Research at
Klipheuwel (Resource Analysis, OM, Pollution,
Noise, Birds, EMC, Condition Monitoring, Energy
Storage, Power Quality)
Commercial 2006 Firming of 1st commercial
site 2006 100MW Business case 2006 onward WEF1
ROD and commercial process Current - Future site
development
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Experience to date Solar electric
Resource assessment 1999-2001 high-level resource
assessment 2001 onward actual resource
measurements and future site evaluation,
measuring both global and direct insolation
Research PV Studies on technologies,
manufacturing and customer issues CSP Distributed
Options Technology evaluations, Dish Stirling
research programme Central Stations Technology
option evaluation, plant modeling, production
estimation, local manufacturing, feasibility
assessment and business case
Implementation PV Significant experience in all
aspects related to PV installations, from system
designs to input on standards. CSP Installation
of a Dish Stirlng system and commercial case for
a 100MW facility
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Experience to date Solar water heating (SWH)

• Eskom has been active in the area of solar water
  heating for many years.
• Activities in the 90s were focussed on
  assessments of different systems and attempts to
  develop lower cost SA-based units.
• Subsequent work was aimed at understanding the
  requirements from the systems and the behavioural
  impact on the consumer as such several pilot
  installations were made.
• The focus changed slightly as the SWH systems
  were not an attractive option to the residential
  consumer, given the low cost of electricity. As
  such, the use of SWH systems from a commercial
  and industrial perspective was considered.
• Current efforts are aimed at increasing the
  uptake significantly. Efforts are focussed not
  only on significantly increase the number of
  systems installed, but also see the accreditation
  of suppliers and registration of installer
  significantly enhanced a key factors in enabling
  higher market penetration.

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Experience to date Ocean Energy
Ocean Wave High-level resource assessment
completed in 2002. Technology evaluation and
assessment since 2000 ongoing. Currently
involved with a detailed site selection and
resource mapping exercise.
Ocean Current Ocean current measurements ongoing
since May 2005, with assistance from
MCM. Currently developing flow models to
understand the resource and impact on it from
generation.
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Experience to date - Biomass
Bagasse Limited experience sugar industry has
expressed its interest to become IPPs for some
time, hence limited opportunity for own Eskom
generation
Wood-waste High-level resource assessment
completed. Studies done on existing sawmills,
volumes and opportunities for generation.
Municipal Solid Waste Developing an understanding
of international projects Investigation into
waste volumes and composition at existing
landfill sites Technology assessments to utilise
the available resource Completion of feasibility
studies
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Technology Status

• IEA View - Maturity of Renewable Energy
  Technologies
• Conceptually, one can define three generations of
  renewables technologies, reaching back more than
  100 years.
• First-generation technologies emerged from the
  industrial revolution at the end of the 19th
  century and include hydropower, biomass
  combustion, and geothermal power and heat some
  of which are still in widespread use.
• Second-generation technologies include solar
  heating and cooling, wind power, modern forms of
  bioenergy, and solar photovoltaics. These are now
  entering markets as a result of RDD investments
  by IEA member countries since the 1980s. The
  initial investment was prompted by energy
  security concerns linked to the oil price crises
  of that period but the enduring appeal of
  renewables is due, at least in part, to
  environmental benefits. Many of the technologies
  reflect revolutionary advancements in materials.
• Third-generation technologies under development
  and in implementation include concentrating solar
  power, ocean energy, enhanced geothermal systems,
  and integrated bioenergy systems.

Source IEA Renewables in Global Energy
Supply, IEA Fact Sheet, January 2007
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Status Application
Strategic fit Baseload? Mid-merit? Peaking?
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Technology Assessment - Solar Cells (Photovoltaic
Devices)

• Application
• Off-grid installations distributed generation.
  Eskom impact Low
• Power Range
• Individual cells range from a few Watts to about
  200W
• Load Factor
• Depends on battery storage. If solar only then
  25
• Life of Plant
• 20 years
• Cost of Generation (relative to other renewables)
• High
• Footprint
• 100MW would require app 74km2 if placed flat.
  Significantly less if mounted.

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Technology Assessment - Wind

• Application
• Grid connected supply. Eskom impact
  Medium/High
• Power Range
• Industry standard 2-3MW / turbine. Plant sizes
  of 50-100MW
• Load Factor
• Depends on site. Avg 22-28.
• Life of Plant
• 20 years
• Cost of Generation
• Moderate
• Footprint
• 100MW would require app 20km2

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Eskom Impact Concentrating Solar Power Central
Receiver Technology

• Application
• Grid connected supply. Eskom impact High
• Power Range
• Plant sizes of 100-200MW
• Load Factor
• Depends on site and storage, app 70.
• Life of Plant
• 35 years
• Cost of Generation
• Moderate
• Footprint
• 100MW would require app 4km2

20
Eskom Impact Bioenergy Generation using wood
waste or Bagasse

• Application
• Meeting internal power requirements, also grid
  supply. Eskom impact Small/medium
• Power Range
• Plant sizes of 5-40MW
• Load Factor
• App 75.
• Life of Plant
• 30 years
• Cost of Generation
• Low
• Footprint
• Depends on resource and project.

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Eskom Impact - Ocean Energy Ocean wave Current

• Application
• Grid connected supply. Significant future
  option. Eskom impact moderate/high
• Power Range
• Single units 1 to 2MW.
• Ocean wave 5 to 20MW. Ocean Current large
  scale range
• Load Factor
• Ocean wave 30 to 50
• Ocean current 70
• Life of Plant
• 20 years
• Cost of Generation
• Moderate/high

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Positioning Renewables in Eskom

• Even though the global economic situation has
  seen a decrease in the demand for electricity,
  Eskom remains committed to its expansion
  programme significant investments are required
  resulting in capital prioritisation.
• As far as new generation is concerned, the main
  current focus is on baseload additions.
• As far as providing baseload options is
  concerned, few renewables are capable of load
  factors required from baseload plant CSP and
  the biomass-based options being the only real
  options to consider. However, these options have
  to be developed to a confidence level similar to
  that of other technologies to be seriously
  considered in decision making.
• Options that have relatively low capital
  requirements and short lead times, e.g. wind can
  play a role while longer term options are
  developed.
• The development of a low cost Solar Water Heating
  option has to be encouraged and uptake
  stimulated.
• Research has to continue to drive new options
  forward, especially amongst the ocean power
  solutions, to deliver the next options for
  implementation.